1. Field of the Invention
The invention relates to the field of door locking systems and, in particular, to a system that unlocks the door from a remote location and the door is automatically set to re-lock upon the opening thereof.
2. Description of Related Art
There has long been a need for a device to unlock a door to a room from a remote location and provide for an indication at the remote location of the status of the door. The most obvious example are public rest rooms in gas stations. Often gas stations are operated by a single proprietor. For safety purposes, the proprietor is obviously required to remain next or near the cash register. In many gas stations that offer only self service gas, they remain in a bullet proof booth. Additionally, there is a need to maintain the rest room in a locked condition, as a safety precaution for patrons. In the past, the door was kept locked and the patron had to request a key from the proprietor. This proved unacceptable, for many people did not return the key. Even if they did, there was no way to tell whether the door was in fact closed, let alone locked.
U.S. Pat. No. 563,724, "Annunciator System For Buildings" by J. M. Arthur solved the door status problem. J. M Arthur's solution is an electrical door lock indication system that would indicate the status of the lock at a remote location. However, this invention did not address the need for locking the door after an individual left the room. In U.S. Pat. No. 4,453,390, Combination Lock Monitoring System" by P. G. Moritz, et. al. a system is disclosed for monitoring the condition of a combination lock; however; it had the same short of short comings as the J. M. Author system.
In U.S. Pat. No. 3,455,127, "Lock Control System" by H. Simon a system is disclosed for unlocking a door from a remote location. In this system, actuation by a key from the remote location electrically actuates a door retainer (striker) to unlock the door for a set period of time, thereafter the door would automatically relock. However, this system has proven to have several short comings, which include the fact that often the rest room is located some distance from the proprietor and, thus, the door often relocked before the patron reached it. In addition, no indication is provided at the proprietor's station that the patron has entered the rest room or that the door has relocked. Sometimes rest rooms are used for illegal transactions and the "patron" has kept the door to the rest room open so that others could join in. Thus, it is important for the proprietor to know the status of the door (unlocked, locked and open). In U.S. Pat. No. 4,994,722, "Automated Door Locking System For Aircraft Lavatory" by D. C. Dolan, et. al. a system is disclosed for locking a lavatory door on an aircraft from a remote location (pilot compartment). An infrared sensing system is use to determine the presence of a person in the lavatory and if it is not in use, the door is locked. If in use, the system is recycled until the person is no longer sensed within the lavatory. However, while this system could be adapted to provide locking of the a rest room and the like from a remote location, it is to complicated and expensive for us in most applications such as rest rooms for gas stations and the like.
Thus, it is a primary object of the invention to provide a door locking system that provides for the unlocking of the door from a remote location.
It is another primary object of the invention to provide a door locking system that provides for the unlocking of the door from a remote location and automatic resetting of the door to a locked condition upon the opening of the door.
It is a further object of the invention to provide a door locking system that provides for the unlocking of the door along with its status from a remote location.